What does it do?

iCompose interface is the answer to the following questions:

How does it work?

An implementation of iCompose interface is used to compose both success and error responses with two different methods:

namespace Luracast\Restler;

interface iCompose {
     * @param mixed $result can be a primitive or array or object
    public function response($result);

    public function message(RestException $exception);

How to customize

There is a default implementation of this interface named Compose returns the success response as such, it formats the error message as follows

if your exception is as follows

throw new RestException(
  'invalid user', 
  ['error_code' => 12002]

The error response in production mode is

  "error": {
    "code": 400,
    "message": "Bad Request: invalid user",
    "error_code": 12002

Note:- the third parameter of RestException is an array of properties which is appended to the response

Additional debug information is returned when restler is running in debug mode. It can be turned off by using Compose::$includeDebugInfo=false; otherwise the response will be

  "error": {
    "code": 400,
    "message": "Bad Request: invalid user",
    "error_code": 12002
  "debug": {
    "source": "VerifyUser.php:115 at validate stage",
    "stages": {
      "success": [
      "failure": [

Taking full control

You can replace the default iCompose implementation with the following configuration

Luracast\Restler\Defaults::$composeClass = 'MyOwnCompose';

Take a look at the Luracast\Restler\Compose class. Ideally just copy and paste the code from that and make your changes.

For example, your response method could be the following to provide a success property and data property.

class MyOwnCompose {
    public function response($result)
        return ['success' => true, 'data' => $result];